Intermittent HDMI cable connection

[Lucid]

@Sureitsoff? , I don't have a preferred brand as such. I've learned from experience that most resellers and trade suppliers haven't the first clue about the HDMI cabling they sell. They just go off whatever the manufacturer tells them, and often with bulk-purchased Far-East-sourced cabling the manufacturers themselves make it up half the time.

With the High Speed (1080p) cables they'd get a few of the shorter lengths HDMI certified, and then just pretend that everything was even up to their maximum lengths. You couldn't trust the certification claims unless you were paying top whack for Chord or Wireworld or some other premium brand. It was very much a case of suck it and see, but before we started to switch to running 4K UHD you'd find that most basic cables would run 1080p/60Hz just fine up to 15-20m.

Everything changed again though when UHD came in. Suddenly it became a problem trying to send UHD (2160p) 60Hz with HDR more than 3-5m. Even now, and especially for projector owners or those wishing to hide the electronics away in some concealed AV it's still a challenge to get reliable signal transmission at anything more than 5-6m with lower-priced UHD-rated cables.

 

[Corazones]

Thanks to you all for so many helpful suggestions and photos.

At the risk of sounding really dumb, I've got a box full of all sizes of cable clips and ties... yet I've never come across an adhesive cable tie. That's certainly worth considering, as there are no vent slots nearby through which I could slide a normal cable tie.

To make the position clearer, here's a photo:

You will see that the plug is horizontal; I would guess that means that a right-angle adaptor could be slightly less effective as the leverage is across the width of the plug, rather than along its length which would have better resisted movement.

Incidentally, the problem arose while the movable bracket remained in its usual viewing position, and the problem arose without the added complication of moving the TV's angle, which is why I didn't think it worth mentioning.

The SCART plug can of course be removed if that proves necessary, I rarely use the DVD player anyway. I did even consider taping the HDMI plug to the SCART, with or without a small block of wood between them, but that plug has a bit of movement too. If only more plugs could be secured with side screws like the old printer connectors!

Lucid, your photo is very clear and helpful; if I'm not mistaken, by putting a ruler up to the image of the two plugs, the short plug also had a shorter metal insert part. You'll see in my photo that this is showing - the plug doesn't quite bottom out, and I think the fact that the body of a short plug would meet the rear of the TV might well add to stability. I think that is the first thing to try - if I can track one of these down.

Anyway, I'm overwhelmed with gratitude for all that great advice, and I've never pressed so many Thanks buttons before. I'll continue following the thread of course, in case more suggestions are on their way, and - once I solve the problem for good - I'll report back.

Thanks again,
Alec

 

[Sureitsoff?]

it is not an adhesive cable tie it is actually a cable tie base that you stick to the tv etc and thread the cable through it and hold the cable to the base
https://www.toolstation.com/adhesive-base-for-cable-ties/p18700?searchstr=cable tie base

make sure the surface you stick them to is clean or they might not stick well

this adapter will make the cable go to the same side as the scart lead and the network cable
https://www.ebay.co.uk/itm/172866751719?hash=item283fa94ce7:g:krMAAOSwJr1ajz9E

 

[Corazones]

RESULT! Thank you all so much for your valued suggestions. The various references to cable ties were the clue that made me think.

If you refer back to my photo, you'll see the SCART plug just below the HDMI plug (and parallel to it). I thought it was too loose to be of any help in providing stability, but I tried anyway. I wedged a block of hardwood, cut exactly to size, between HDMI and SCART plugs. Then I put a plastic cable tie around the whole lot and tightened it very well. Problem solved.

Now I can even swing my adjustable wall clamp in any direction I want - not a thing I often do - and the sound and picture still don't even flicker.

If that hadn't worked, I was going to fashion an oblong plastic washer to take up the tiny space between the metal body and plug, as I thought that complete contact of the plug against a flat surface would reduce the ability of the plug to swivel. Then I'd have worked my way through all your other helpful suggestions.

Thanks again to everyone,

Alec.